Cross-flow fans used in indoor units of air conditioning systems, for example, have plural blades that extend in the longitudinal direction of the cross-flow fan and are disposed between annular partition plates disposed on both longitudinal direction ends of the cross-flow fan. Additionally, as disclosed in JP-A No. 2014-47772, for example, there are cases where a reinforcement ring is disposed between support plates to reinforce the strength of the plural blades.